1.(a) Field of the Invention
The present invention relates to an improvement in check valve in general and preferably in check valve of the type used in massaging or hydromassaging apparatuses (especially therapeutic baths). Those apparatuses or baths are of the type provided with a plurality of openings positioned below a level of water, and provided with a check valve mounted across each of said openings. The invention also relates to massaging or hydromassaging apparatuses (or therapeutic baths) in which each check valve is the aforesaid improved check valve.
1.(b) Brief Description of the Prior Art
As disclosed in U.S. Pat. No. 4,249,522, there exists a hydromassaging apparatus comprising in combination a tub, compressed air supply means located adjacent the tub, longitudinally extending air distribution duct means secured to the outside surface of the tub, the duct means also comprising air distribution branches and a plurality of small openings extending through the tub from the air distribution duct means, the openings being evenly spaced apart.
In Applicant's Canadian patent applications Nos. 2,005,276-7 and 2,018,117-6, there is disclosed a check valve which is intended to be positioned across a corresponding opening (especially a side opening) of a hydromassaging apparatus (advantageously a therapeutic bath of the type described in U.S. Pat. No. 4,249,522) in order, when a check valve is mounted across each opening of the apparatus, to prevent any introduction of water contained in the tub of the apparatus toward duct means of said apparatus. Such a check valve is efficient to keep dry said duct means and thus minimize the risk of having a growth of bacteria and/or fungi in said duct means. However, because each check valve is provided with at least one recess, at its end in contact with the water contained in the tub, it was noted that when the tub is emptied, some water, especially waste water, remained in aforesaid recess, especially when the check valve is mounted across an opening provided in the bottom of the tub. Also, because a check valve is relatively small, it is almost impossible to easily clean said recess after each use of the apparatus. Thus, bacteria and/or fungi may be allowed to grow in said recess. Such a drawback negatively affect the sanitariness of the apparatus using such a check valve.
The published PCT patent application No. W089/10112 discloses an air excitation hydromassage bath system designed for use in an ordinary bathtub. The system utilizes an air control array of adjustable nozzle assemblies installed on the bottom of the tub. The air control system includes two or more arrays of adjustable nozzle assemblies. Each nozzle assembly is provided with a cap, a body and a foot as well as an additional check valve located between the cap and the body. The cap and the body are configured to permit adjustability of air flow from substantially off to substantially full flow and also provide means for directing air flow laterally and/or vertically.
The additional check valve disclosed in this PCT application is a conical shaped membrane having a large periphery which makes possible the risk, in presence of dirt, oil and/or soap deposits, to stick to the body. Also, because there is a volume between the cap and the membrane, water (especially waste water) may remain in that volume which cannot be cleaned, and there is a substantial risk of having a growth of bacteria and/or fungi therein. Furthermore, it is compulsory, with this check valve, to have a cap in order to create jets of air bubbles in water and prevent the membrane to be damaged or rendered non-operable (especially when the check valve is positioned in the bottom of the tub) because someone could walk thereon.